Today in the shop (turning some aluminum)
Posted: Fri Mar 13, 2020 8:27 pm
Aluminum tubing that is. I wouldn't call this a complete success as the finish is not all that great but it looks to be functional.
I played with several ways of doing this and most of them were painfully slow. I then pulled out the parts shown and tried a couple of cutters and finally decided on a carbide cutter and running at about 500 rpm. I didn't try at 700 ish but it might works as well. At 500 it was cutting and not throwing chips every where so I stopped there after getting as high as 600.
The piece of plywood that works as a depth stop was adjusted with some small hammer taps until it was cutting about as well as I expected. You can do some fine adjustments on tool by cheating a little.
I have 6 that I need and 3 done but I'm done for the night. Might be a couple of days to wait to finish the last 3 as it is expected to be colder tomorrow and Sunday I have other plans.
For those who don't know, those are parts from the shopsmith lathe duplicator.
One issue that I found is the casting is slightly curved where it goes against the plywood so that movement is working against you the whole way. I'd like to fix that with some grinding but not now. One might be able to make a sub-base for it and but some adjustments for depth of cut which would be the right way to do it.....
I don't know the actual outside diameter of the tubes but they are called 20mm. I don't know what they are being turned down to but they have a go/no go hole they have to fit in and if the whole project works I will farm out some tubes to be done with a nice finish. For the testing these will do fine.
My brother has an old metal lathe he is willing to give me but it needs a motor and some tender loving care to get it working and even if I get it I have not place to put it. It was given to him so who knows what other problems might show up that would be difficult to deal with.
Ed
I played with several ways of doing this and most of them were painfully slow. I then pulled out the parts shown and tried a couple of cutters and finally decided on a carbide cutter and running at about 500 rpm. I didn't try at 700 ish but it might works as well. At 500 it was cutting and not throwing chips every where so I stopped there after getting as high as 600.
The piece of plywood that works as a depth stop was adjusted with some small hammer taps until it was cutting about as well as I expected. You can do some fine adjustments on tool by cheating a little.
I have 6 that I need and 3 done but I'm done for the night. Might be a couple of days to wait to finish the last 3 as it is expected to be colder tomorrow and Sunday I have other plans.
For those who don't know, those are parts from the shopsmith lathe duplicator.
One issue that I found is the casting is slightly curved where it goes against the plywood so that movement is working against you the whole way. I'd like to fix that with some grinding but not now. One might be able to make a sub-base for it and but some adjustments for depth of cut which would be the right way to do it.....
I don't know the actual outside diameter of the tubes but they are called 20mm. I don't know what they are being turned down to but they have a go/no go hole they have to fit in and if the whole project works I will farm out some tubes to be done with a nice finish. For the testing these will do fine.
My brother has an old metal lathe he is willing to give me but it needs a motor and some tender loving care to get it working and even if I get it I have not place to put it. It was given to him so who knows what other problems might show up that would be difficult to deal with.
Ed